PTL 1 discloses an antenna device including: a circuit board having a power amplifier; and a planar inverted F antenna (PIFA). In the antenna device disclosed in PTL 1, the PIFA antenna includes: an antenna body; two attachment surfaces which are a surface to be attached to a ground plane of the circuit board and a surface to be connected to an output terminal of the power amplifier; and an attachment foot part that connects the two attachment surfaces and the antenna body to each other. The antenna body of the PIFA antenna is disposed opposite to the ground plane of the circuit board. In the antenna device disclosed in PTL 1, heat generated in the power amplifier that is a heat generating component is conducted to the antenna body via the attachment foot part, and is thereby radiated.